Copyright 1997
Welch Allyn Inc.
4341 State Street Road
Skaneateles Falls, NY 13153-0220
Part Number 495623Rev A.
Page 2
Revision (History) Page
Rev.Description of ChangeECN #DateInitial
ANew Release5-344571/14/97JSJ/MD
Service Manual Welch Allyn Fiber Optic Hea dlight System
IntroductionPage 2
Page 3
To Service Personnel:
The information in this manual is subject to change without notice and should
not be construed as a commitment by Welch Allyn, Inc.
Welch Allyn assumes no responsibility for any errors that may appear in this
manual. If the product and/or its operation varies significantly from any
description herein, please contact the Welch Allyn Product Service Department
at 4341 State Street Road, Skaneateles Falls, New York 13153-0220, 1 800 6699771, (315) 685-4445
This product has been designed to provide a high degree of safety and
reliability. However, we can not guarantee against the deterioration of
components due to aging and normal wear.
All service and repairs must be performed by authorized Welch Allyn personnel
or agents, using Welch Allyn replacement parts. Failure to do so will invalidate
the product warranty.
Authorized service centers should refer to repair specification for proper test
and device history record requirements.
Please refer to the product warranty for specific coverage.
Welch Allyn, Inc.
Medical Products
4341 State Street Road
Skaneateles Falls, New York 13153-0220
USA
1 800 669-9771
(315) 685-4445
Service Manual Welch Allyn Fiber Optic Hea dlight System
IntroductionPage 3
If you have technical questions, or need other assistance, call Welch Allyn
customer service personnel at
1-800-669-9771.
Cleaning Warnings:
DO NOT IMMERSE the Luminaire in any type of liquid. Do
not spray it heavily with any type of liquid. The liquid might enter the Luminaire
and create a service problem. DO NOT AUTOCLAVE the whole Luminaire. Only
the Joystick is autoclavable separately.
Follow Cleaning and Maintenance instructions in Owner's Manual PN495608.
Caution
light source. Clean exterior surfaces of Luminaire, headband, and fiber optic bundle by
wiping clean with any of these solutions: Banicide, Cidex, Cidex Plus, Cidex 7,
Metracide, 10% Wescodyne, 10% chlorine bleach, 70% Isopropyl alcohol, Wavecide01, mild soap and water solution.
: Turn off light source before disconnecting fiber optic bundle from headlight or
Service Manual Welch Allyn Fiber Optic Hea dlight System
IntroductionPage 4
Page 5
Table of Reference Drawings (Appendix A)
Drawing #Description
495540Welch Allyn Headlight Main Assembly . . .
495570
495550
Note that drawings within this manual are for reference only. Consult factory for
current revisions.
Suspension / Luminaire Assembly ......
Luminaire Assembly.................
Service Manual Welch Allyn Fiber Optic Hea dlight System
IntroductionPage 5
Page 6
Section 1Disassembly & Reassembly
Abstract of disassembly and reassembly of 49540 Luminaire:
The whole luminaire can be disassembled with the exception of the Mirror and
back plate which are pinned and glued to the bottom housing. If moisture is
present in the luminaire, replace the iris assembly and clean the lenses by
following instructions in this manual. With the exception of the mirror, all
components can be replaced as necessary.
The following is the process for completely disassembling and reassembling the
luminaire for 'O' ring replacement. "O" rings are used not to seal out moisture
but to provide a smooth moveable connection between parts. Only replace 'O'
rings if they are worn, cracked, stretched out or missing. If the iris control sleeve
is too loose, then the O rings have failed.
1.1Removing O rings:
__
Unscrew
joystick from the lower housing.
__Unscrew
or equivalent. The bezel is glued on.
__
Unscrew
__
__
the top cap off of lens housing.
Pull
Remove
1.2Remove Bottom Housing:
__
Unscrew
held together using a thread locking adhesive. Use of a collet
will be needed to break the bind of the thread locker.
Note: the back plate and the mirror can not be replaced as they are pinned and
glued into the bottom housing. If the mirror is broken or loose, replace the
complete bottom housing assembly.
1.3Remove Iris Assembly:
__
Unscrew
Use 1/16" flat blade screwdriver.
the bezel from the luminaire. Use the appropriate collet
the top nut. Use collet or equivalent.
O rings.
bottom housing from lens housing. These parts are
the small pin in the side of the control sleeve.
Note: If the iris pin is sheared, it might be removed by grabbing it
with a small diagonal cutters and unscrewing it. If not, replace lens
housing Asy.
__
__
__
control sleeve from the lens housing.
Pull
Remove
Unscrew
'O' rings.
the iris retaining nut using the Welch Allyn tool
T-14452 or equivalent.
Service Manual Welch Allyn Fibe r Optic Headlight SystemPage 6
Page 7
Section 1Disassembly & Reassembly
__
Heat
attempting to loosen it. The setscrew can be heated by
inserting the hex key into the setscrew and applying heat from a
soldering iron to the hex key wrench.
__
Unscrew
.035" hex key.
__
Remove
1.4Remove Condensing
Lenses and spacers
__
Heat
threadlocker that is used. The setscrew can be heated by
inserting the hex key into the setscrew and applying heat from a
soldering iron to the hex key wrench. If the set screws become
stripped, then the entire lens and iris assembly will need to be
replaced.
the 2-56 setscrew holding the iris in place before
the 2-56 setscrew holding the iris in place. Use a
the iris.
the three 2-56 setscrews before loosening due to the
__
Unscrew
the three 2-56 setscrews from the lens housing. Use a
.035" hex key.
__
Remove:
the spacer, condensing lens, spacer, and small
condensing lens.
Service Manual Welch Allyn Fibe r Optic Headlight SystemPage 7
Page 8
Section 1Disassembly & Reassembly
Re-assembly of model 49540 Luminaire
Special notes for reassembly of Luminaire:
1.5Install Condensing
Refer to assembly drawing 495550 in this manual.
Use new set screws and 'O' rings when reassembling luminaire.
Remove any threadlocking adhesive from parts by chasing threads with taps or
dies.
Do not touch lenses or mirror with fingers. Clean them with cotton swabs and
lens cleaner.
Lenses and spacers
__
Insert
convex portion is up.
__
Insert
large diameter is facing up. Push it down onto the condensing
lens.
__
Insert
the lens housing on top of the condensing lens spacer.
clean condensing lens into the lens housing so that the
a condensing lens spacer into the Lens housing so the
the next lens (This lens is the same on both sides) into
1.6Install Iris assembly
__
Insert
Push it down so it seats on the lens fully.
__
Compress
equivalent. At the same time, dip a set screw into the Loctite 425
threadlocker and
housing using a .035" Hex wrench.
__
Install
Iris assembly facing upwards. There is a slot in the side of the Iris
which has a tapped hole located in it.
the slot in the Lens housing.
__
Screw
Iris; finger tighten.
after the Iris is locked into place with the Iris retainer.
__
Insert
of the tool is in the Iris opening and the rubber part of the tool rests
on the Iris.
same time, rotate the tool clockwise. Rotating the tool will cause
the Iris pin tool 14600 to rotate until it contacts the end of the slot in
the lens housing. Continue rotating the tool until the Iris opening
closes down onto the pin of T14448.
the Iris Spacer into the Lens housing chamfered end first.
the spacers and lenses together using T14601 or
Install
the Iris into the lens housing, with the retaining clip of the
T14600 through the slot in the lens housing and into the
T14448 into the Lens housing so that the pin in the center
Apply
light downward pressure to T14448 and at the
it into one of the three holes in the Lens
this tapped hole with
Align
Note:
This is temporary and will be removed
__
Rotate
contacts the opposite side of the slot. Hold 14448 steady while
performing this operation.
Service Manual Welch Allyn Fibe r Optic Headlight SystemPage 8
the Iris counter clockwise using T14600 until the tool
Page 9
Section 1Disassembly & Reassembly
__
Install
a set screw with threadlocker Loctite 425 into the top
threaded hole on the Lens housing using a .035" hex wrench; while
at the same time,
Note:
__
Over tightening of this set screw will cause the Iris to bind.
Remove
tool T14448.
apply
threadlocker to the Iris retainer threads, then
firm pressure downward with T14448.
Apply
2 to 3 drops of Loctite 425
Install
the Iris retainer
using T14452.
Note:
When the Iris is at full closed position, a .090" diameter pin should not go through
the hole in the center of the Iris. Open and close the Iris; the operation should be
smooth.
1.7 Assemble Bottom Housing to Lens Housing
__
Open
the Iris to full open position and
out any dust in the
blow
lens housing assembly using an Aero duster or equivalent.
__
Close
__
Blow
Iris.
any dust out of the bottom housing assembly with an aero
duster.
__
Apply
3 to 4 drops of Loctite 425 threadlocker to the large
external threads of the lens housing, and
housing.
Tighten
collet.
__
Place
the fiber optic cable leading from the Solarc Light Source
into the top of the luminaire assembly.
__
Inspect
white piece of paper. Also
operation. Any small dust spots not noticed within 2 seconds are
generally acceptable. Large, dark or hair-like spots are not
acceptable.
1.8 Control Sleeve and Top Cap
__
Install
(2) large O-rings into the lower grooves on the Lens
Housing.
__
Install
(1) large O-ring onto the top of the first shoulder of the
Lens Housing.
screw
it into the bottom
the assemblies together with the appropriate
the spot for any dirt or dark spots by shinning onto a
Rotate
the Iris and check for proper
__
Apply
__
Assemble
to the O-rings.
a light coat of Grease to all (3) O-rings.
the Control Sleeve over the Lens Housing and down
Rotate
the Control Sleeve so that the hole in the
side of it is positioned above the threaded hole in the Iris; seen
through the slot in the Lens Housing.
__
Service Manual Welch Allyn Fibe r Optic Headlight SystemPage 9
Control Sleeve down over the O-rings until seated; being
Push
Page 10
Section 1Disassembly & Reassembly
careful not to rotate the parts.
__
Apply
(1) drop of Loctite Adhesive to the threads of an Iris Pin
and install through the hole in the Control Sleeve and into the Iris.
Tighten w/ a screw driver until flush or just below.
Rotate
__
Control Sleeve back and forth to spread grease and
check for freedom of movement.
Install
__
(1) large O-ring onto the Lens housing and push down until
seated on top of the Control Sleeve.
Install
__
(2) large O-rings into the lower exposed grooves on the Lens
Housing.
Install
__
(1) small O-ring onto the Lens Housing so that it sit on the
shoulder just above the last Large O-ring.
Apply
__
__
Apply
a generous coat of Grease to the 2 lower O-rings.
a coat of Grease to the inside of the Top Cap.
Install
__
a Top Cap onto the Lens Housing so it rests on
the
O-rings.
Rotate the Top Cap while pushing it down over the O-rings. Continue
until seated.
Install
__
__
Apply
(1) Small O-ring down on top of the Top Cap.
2-3 drops of Loctite 425 Threadlocker to the Lens Housing
threads.
Install
__
the Top Cap Nut onto the Lens Housing and tighten with the
appropriate collet or equivalent.
Rotate
__
the Top Cap a few turns to make sure it rotates smoothly.
Service Manual Welch Allyn Fibe r Optic Headlight SystemPage 10
Page 11
Section 1Disassembly & Reassembly
Abstract of disassembly and reassembly of 49540 Luminaire Suspension:
The following is the process for adjusting or repairing the luminaire suspension.
In most cases the end user will probably indicate that the luminaire no longer
stays where it is put. This condition is caused by wear to the friction washers in
the suspension mechanism or loosening of the assembly screws. The assembly
screw(s) can be tightened to compensate for the wear of the washers or in
severe cases, the washers will need to be replaced.
Special notes for repairing the Luminaire Suspension:
Refer to assembly drawing 495570 in this manual for proper reassembly and
torque specifications.
Reapply threadlocking adhesive (Loctite 425) to any screws that are tightened or
loosened.
__
Remove
the setscrews located inside the three pivot nuts, using
a 1/16" hex key.
__
Loosen
the three Pivot nuts to break any of the threadlocker
free so that the nut turns freely, and blow out any loose debris left
from the old threadlocker.
__
Tighten
the three Pivot nuts to the specified torque as
described on drawing 495570.
__
Apply
setscrew and
a drop of Loctite 425 threadlocker onto the threads of a
install
it into one of the pivot nuts. Tighten with a
1/16" hex wrench. Repeat for the remaining two screws.
Service Manual Welch Allyn Fibe r Optic Headlight SystemPage 11
Page 12
Section 2Headband Adjustments & Repair
Abstract of adjustment / repair of the Headband:
The following is the process for adjusting or repairing the headband. There are
only two replaceable components of the headband assembly, the three vinyl
pads (1set) and the fiber-optic clips. The fit adjustment controls can be adjusted
if the knobs are too hard to turn or if the headband will not maintain it's fit
(Loosens).
Special notes for repairing the Headband:
Refer to assembly drawing 495540 in this manual for further details.
2.1 Comfort/Fit Adjustment Knob:
2.2 Fiber Optic Clips:
If the vinyl pads need to be removed and reused, be sure to release snaps by
pushing a fingernail or equivalent between the two halves of the snap. The vinyl
is extremely thin and will tear if pulled on directly.
__
Tighten
headband continues to loosen.
__
Loosen
knob is too hard to turn.
__
Remove
assembly. See note above.
__
Unscrew
and
Remove
the screw in the center of the adjustment knob if the
the screw in the center of the adjustment knob if the
the vinyl pad on the top support of the headband
the two screws that hold the respective clip in place
the clip.
__
Reassemble
in reverse order.
Special Notes for the Fiber Optic Bundle:
The Fiber optic bundle (49543) is a multi-fiber cable which transmits the light generated at the light
source into the Luminaire Assembly. There is no repair for this item. It must be replaced if the fibers
become damaged.
Note:
Broken Fibers?:
Service Manual Welch Allyn Fibe r Optic Headlight SystemPage 12
Refer to owner's manual (495608) for cleaning and disinfection.
__Hold
areas are broken fibers. The fiber optic cable will need to be replaced if the dark
area covers 20% or more of the entire bundle surface.
one end of the fiber bundle up to a light and look at the other end. Dark
Page 13
Section 3Tools & Equipment
Tools and Equipment List
General purpose tools / supplies:
1/16" hex key
.035" hex key
Peer #7 tweezers
# 4 Flat Blade screwdriver
#2 Phillips screwdriver
#1 Phillips screwdriver
Collet Block
5C Collet for Top Nut Cap (.382")
5C Collet for Lens Housing (.438'')
5C Collet for Bezel (1.06")
Jeweler's's flat-blade screwdriver (1.5mm x 40mm) for Iris Pin.
Aero Duster ("canned air") or equivalent.
moisture that are often found in compressed air.
Welch Allyn tools and fixtures:
T14600: Extended iris pin.